Within the framework of the NIGMS Shared Instrumentation Program, this proposal by the two Co-Principal Investigators Derek Horton and Perry A. Frey requests funds for purchase of a modern, 200-MHz NMR spectrometer that will serve the ongoing needs of active, GM-supported research programs of these investigators, plus the research work of the two additional participants (Lawrence J. Berliner and Robert M. Mayer) in the Core User Group. This instrument is required for provision of high-quality 1H-, 13C, and 31P-NMR spectra on a routine basis to the core-group users, whose research space is contiguously located in one part of the Chemistry Department complex. The Core User Group will generate approximately 50-75% of the service workload on the instrument, and access will be provided to a wider circle (potential user group) of researchers in the Department of Chemistry, in other departments of the Ohio State University, and other qualified investigators in the geographical area of Franklin County, Ohio. Service-technician support on a continuing basis is assured by the Department of Chemistry. The research served by this instrument covers a broad range of programs in the biomedical area that are in progress in the laboratories of the Core User Group members, who collectively direct the research work of approximately 30 graduate students and 10 postdoctoral associates. The research problems are diverse, but have as a common denominator the need for regular, proximal access to a versatile, high-performance NMR instrument that can provide routine data of quality sufficient for use with biological molecules of some complexity to furnish significant information on molecular structure and dynamics. No instrument meeting such criteria is available in any location on the OSU campus nor at any other institution in the central Ohio area.